1. Field of the Invention
The present invention relates to an electronic exchange system which can be maintained by remote control.
2. Description of the Related Art
Recently a private electronic exchange apparatus has employed its microprocessor as a center of control and has been more intelligent and more functional. A private electronic exchange apparatus using a microprocessor comprises extension lines and office lines and has service functions as well as basic functions of exchange connections between the extension lines and between the extension lines and office lines. One of the service functions is a remote-maintenance function.
Though the private electronic exchange apparatus has various service functions such as an increase in extension lines, management of charges for each extension line, and regulation of usable extension and office lines, it requires a data table or the like in order to fulfill these functions. Since the data table has to be altered, deleted, and added in accordance with a variation in circumstances, the private electronic exchange apparatus has the remote-maintenance function.
A private electronic exchange apparatus generally includes an interface to which an operational terminal for transmitting/receiving commands and data can be connected. If a maintenance terminal (a maintenance console) is connected to the interface to send commands and data, a data table in a storage unit of the private electronic exchange apparatus can be changed, added, deleted, etc. The maintenance of the apparatus can thus be performed by the maintenance terminal attached thereto. Otherwise, the maintenance of plural private electronic exchange apparatuses located in different positions can be controlled by remote control from a maintenance control center.
In order to maintain a remote private electronic exchange apparatus, the apparatus is connected to the maintenance terminal of the maintenance control center by means of their private lines, the apparatus is called from the maintenance terminal through its private line, and a command and data are transmitted to the apparatus by operating a keyboard of the maintenance terminal, with the result that data is rewritten, added, deleted, etc.
This remote-control maintenance is very convenient since no maintenance man has to be stationed in a remote private electronic exchange apparatus and necessary measures can be taken by remote control from the maintenance control center whenever the maintenance of the apparatus is required. However, the remote-control maintenance necessitates private lines for connecting the private electronic exchange apparatus and the maintenance terminal. The private lines are used in order to connect the maintenance terminal with the exchange apparatus through an interface. The use of the private lines increases the cost of an electronic exchange system, and it is not efficient to use the lines only for the infrequent maintenance of the exchange apparatus.